16 cantrip list is indeed the most vanilla of the various lists and a decent starting point. I would never run PiF, Tendrils, AdN, and EtW all in the main. At most I would play 3/4 of them. Usually PiF, Tendrils, and AdN. Empty rarely wins me games anymore against experienced Legacy players. As for boarding I usually board my 2 Preordains and 3 Duress and the 15th land. Anymore than that and I feel you're overboarding.